本题目来源于试卷: Unity and Diversity A.1 Water，类别为 IB生物学
[单选题]
What is the most accepted theory for the origin of water onm26 o*c ujk8khrdb5:w/ j3)apkkhwgknr d ,20 Earth?
A. Asteroids from space containing ice arrived on Earth billions of years ago
B. Respiration from early organisms released water into the atmosphere
C. Heat from ancient deep-sea vents catalysed the reaction between hydrogen and oxygen atoms
D. Early volcanic eruptions, released steam into the atmosphere
参考答案: A
本题详细解析:
Asteroids from space, which c dwdj38vtb4fjzti* d8 8q0tb8ontained ice, arrived on Earth. This is the most accepted theory for the origin of water on Earth. This theory, often referbjdt4wi 808q8d8 jtbdvzf* t3red to as the "Late Heavy Bombardment" theory, suggests that during the early stages of the Solar System's formation, a significant number of asteroids and comets, some of which contained water in the form of ice, bombarded the Earth. Over time, as these icy bodies collided with Earth, they contributed to the accumulation of water on the planet's surface. Choice A is correct.
Choice B is incorrect, as water was present on Earth before early organisms were present. Choice C is incorrect because free oxygen atoms were absent in the early atmosphere. Choice D is incorrect because liquid water would need to be present on Earth before it could be converted into steam.
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